title: Effect of a drug holiday on plasma chlorpromazine levels in chronic schizophrenic patients.
abstract: Low chloropromazine (CPZ) levels have been measured in chronically treated schizophrenics. We tested six such patients to determine whether a 2-week CPZ-free period (drug holiday) would improve plasma CPZ levels. We also monitored psychiatric symptoms, autonomic function, and extrapyramidal signs. We found these patients to have low predose CPZ levels that did not change appreciably after the drug holiday. Peak levels following the holiday averaged 28 +/- 7 ng/ml higher than those measured prior to the holiday. Drug holidays are safe and should be examined more thoroughly as a means of improving plasma neuroleptic levels in chronically treated schizophrenics.
mesh_terms: D000328:Adult; D002746:Chlorpromazine / Q000009:adverse effects / Q000097:blood* / Q000627:therapeutic use; D002908:Chronic Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D010302:Parkinson Disease, Secondary / Q000139:chemically induced; D010640:Phenothiazines / Q000627:therapeutic use; D012559:Schizophrenia / Q000097:blood* / Q000188:drug therapy; D013375:Substance Withdrawal Syndrome / Q000523:psychology
chemical_list: D010640:Phenothiazines; D002746:Chlorpromazine